All sexually active women can be vulnerable to hiv infection .
所有性活動頻繁的女性都易感染艾滋病。
Reproducing sexually may disrupt beneficial genetic combinations and lower the mean fitness of offspring .
有性生殖則可能破壞這種有利的基因組合,降低后代的平均適應能力。
When men are sexually interested , they start playing with circular objects .
當男子對性感興趣的時候,他們會開始把玩環形的東西。
Aids is a sexually transmitted disease with no scientific evidence for arthropod transmission .
艾滋病是性傳播疾病,并且不存在媒介節肢動物傳播的科學理論依據。
Performers said they understood the risks of not using condoms but believed current industry practices which involve screening for some sexually transmitted diseases monthly were enough to protect them .